CA1064265A - Digital liquid crystal electronic timepiece - Google Patents
Digital liquid crystal electronic timepieceInfo
- Publication number
- CA1064265A CA1064265A CA258,698A CA258698A CA1064265A CA 1064265 A CA1064265 A CA 1064265A CA 258698 A CA258698 A CA 258698A CA 1064265 A CA1064265 A CA 1064265A
- Authority
- CA
- Canada
- Prior art keywords
- liquid crystal
- circuit
- crystal display
- voltage
- time
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G04—HOROLOGY
- G04G—ELECTRONIC TIME-PIECES
- G04G9/00—Visual time or date indication means
- G04G9/0023—Visual time or date indication means by light valves in general
- G04G9/0029—Details
- G04G9/0047—Details electrical, e.g. selection or application of the operating voltage
-
- G—PHYSICS
- G04—HOROLOGY
- G04G—ELECTRONIC TIME-PIECES
- G04G9/00—Visual time or date indication means
- G04G9/0023—Visual time or date indication means by light valves in general
- G04G9/0029—Details
-
- G—PHYSICS
- G04—HOROLOGY
- G04G—ELECTRONIC TIME-PIECES
- G04G9/00—Visual time or date indication means
- G04G9/08—Visual time or date indication means by building-up characters using a combination of indicating elements, e.g. by using multiplexing techniques
- G04G9/12—Visual time or date indication means by building-up characters using a combination of indicating elements, e.g. by using multiplexing techniques using light valves, e.g. liquid crystals
- G04G9/126—Visual time or date indication means by building-up characters using a combination of indicating elements, e.g. by using multiplexing techniques using light valves, e.g. liquid crystals provided with means for displaying at will a time indication or a date or a part thereof
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Electric Clocks (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A digital liquid electronic timepiece comprises in combination a time counting circuit; a switching circuit for selecting a time signal corresponding to time units of seconds, minutes, hours and dates generated from the time counting cir-cuit; a liquid crystal display device having retardation effect for displaying a time signal in digital form selected by the switching circuit; a voltage generating circuit for generating.
a plurality of different drive voltages for driving the liquid crystal display device; the driving voltage of the liquid crystal display device being changed whenever the time units displayed in the liquid crystal display device are changed.
A digital liquid electronic timepiece comprises in combination a time counting circuit; a switching circuit for selecting a time signal corresponding to time units of seconds, minutes, hours and dates generated from the time counting cir-cuit; a liquid crystal display device having retardation effect for displaying a time signal in digital form selected by the switching circuit; a voltage generating circuit for generating.
a plurality of different drive voltages for driving the liquid crystal display device; the driving voltage of the liquid crystal display device being changed whenever the time units displayed in the liquid crystal display device are changed.
Description
This invention relates to a digital liquid cry~tal time-piece, capable of selectively displaying digitally time units of seoond~, minutes, hours, dates and months, in which each of said time units is displayed in a different colour, whereby it is possible to easily differentiate the units being displayed.
In known digital liquid crystal timepieces, if the time units of seconds, minutes, hours, dates and months were dis-played on one display panel, it is necessary to provide a display portion of two digits for seconds, a display portion of four digits for minutes and hours, and a display portion of four digits for dates and months. Thus a total of ten digits is required in said display device. If each group of digits were constructed to a scale which can be easily read, said display panel become-excessively large. Therefore, it is very difficult to make a small wrist watch such as would be suitable for women.
The present invention is directed to the means for resolv-ing these problems, whereby a display panel employing only four digits is used to display months and dates, hours and minutes and seconds. With such a four digit display, it is possible to obtain a small sized display panel. However, it is very difficult to know the time unit being displayed. It is also necessary to pro-vide an additional means for distinguishing the displayed contents in normal display condition and time adjusting condition. The mounting of a further display has a disadvantage of being impossible to see the display from the stand point of perspective view. It is further possible to obtain a small sized wrist watch having two digits instead of four digits by selectively displaying said time units of seconds, minutes, hours, dates and months.
The object of the present invention is to provide a small sized wrist watch having a small sized display panel by reducing the number of digits in the display panel. Another object of the , , present invention is to provide a time display device having no other display portion for distinguishing the displayed time unit~
rospeotively. A further object of the present invent~on ~ to provide a digital liquid crystal electronic timepiece having a simple display panel. A further object of the present invention is to provide a digital liquid crystal electronic timepiece having a liquid crystal display device capable of displaying time unita of seconds, minutes, hours, dates and months in different colours respectively whereby it is possible to easily distinguish the digits being displayed.
A further object of the present invention is to provide large sized digits in the display panel by reducing the number o$
digits of the display device, whereby it is possible to obtain -colourful digital liquid crystal electronic timepiece by the change of display colour.
Referring now to the accompanying drawings which show a digital liquid crystal electronic timepiece of the present inven-tion:
Figure 1 shows a block diagram of the digital liquid crystal electronic timepiece of the present invention:
Figure 2 shows a characteristic for indicating a retarda-tion effect of the liquid crystal display device;
Figure 3 shows a circuit of one embodiment of the voltage generating circuit in Figure l;
Figure 4 shows a circuit of one embodiment of the switching circuit for selecting the display time signal;
Figure 5, which is on the same sheet as Figure 3, shows a circuit of one embodiment of the switching circuit for selecting the drive voltage of the liquid crystal display device; and Figure 6 shows a circuit of one embodiment of the drive circuit in Figure 1.
Figure 1 shows a block diagram for indicating a digital liquid crystal electronic timepiece of the present invention;
numeral 1 is a time keeping circuit. Said time keeping circuit 1 has an oscillating circuit (not shown) having a quartz element, a dividing circuit (not shown) for obtaining a standard signal of lHz, a time counter (not shown) for generating a time signal corresponding to the time units of seconds, minutes, hours, dates and months after counting said standard signal, and a decoder (not shown) for changing the output from said time counter to a prefer-able coded time signal. Therefore, four kinds of time signals aregenerated from said time keeping circuit 1. Said time keeping circuit 1 is operated by the output voltage of boosting circuit 3 and the battery voltage of the battery 2. Numeral 4 is a voltags generating circuit for generating four different voltages. Said voltage generating circuit 4, one embodiment as indicated in Figure 3, has a terminal al directly connected to the boosted voltage of said boosting circuit 3, a terminal a2 providing a voltage lower than said boosted voltage by the resistance Rl and zener diode ZDl, a terminal a3 providing a voltage lower than said boosted voltage and the output voltage of said terminal a2 by the resistance R2 and zener diode ZD2 and a terminal a4 providing a voltage lower than said boosted voltage and output voltage of said terminal a3 by the resistance R3 and zener diode ZD3. The boosted voltage is provided at terminal al; however, the output voltages of said terminals a2, a3 and a4 correspond to the zener voltages of said zener diodes ZDl, ZD2 and ZD3, and become lower respec-tively~ The resistance values of resistance Rl, R2 and R3 deter-mine the electric current of flowing to the zener diodes ZDl, ZD2 and ZD3, and are selected for generating voltages corresponding to the zener diode voltages to said terminals a2, a3 and a4.
` 1064265 - In Figure 1 the time signal of minutes, hour~, dates and months generated from said time keeping circuit 1 are applied to the switching circuit 5, and four voltages of the voltage gener-ating circuit 4 are applied to the switching circuit 6. The switching circuits 5 and 6 are controlled by a mechanical switch 7, for example the switch being operated by the operation of the stem of the electronic timepiece or other operational switch.
Said switching circuit 5 selects one signal of minuteQ, hours, dates and months and applies the selected signal to the driving circuit 8; the switching circuit 6 selects one of four voltages .
and applies it to the driving circuit 8. According to the present invention, when said switching circuit 5 selects the time signal of months, said switching circuit 6 selects the voltage from the terminal al of said voltage generating circuit 4. When said time signal of dates is selected, the voltage of terminal a3 is selected:
further when time signal of minutes is selected, the voltage of ~-terminal a4 is selected.
The driving circuit 8 drives the liquid crystal display device 9 with the voltage selected by said switching circuit 6, ; 20 and the time signal selected by said switching circuit 5 is dis-played by the liquid crystal display device 9. The liquid crystal display device 9 is composed of two digit display portions, each display portion having seven alpha-numeric type segment electrodes and one common figure electrode. The liquid crystal employed in said liquid crystal display device 9 has a retardation effect, the colour of said liquid crystal being changed by the difference of drive voltages.
Referring now to Figure 2, which shows the retardation effect of said liquid crystal, the X axis indicates the drive ~ltaqe ~pplied to the liquid crystal, the Y axis indicate~ the intensity of transmission light, the curved lines G, B and R
, ............ . .
,. :
.
10642~5 indicate the change of intensity of transmission light against the change of drive voltage of green, blue and red. At the voltage Vl, the intensity of transmission light of red is maximum whereby the displayed colour is red. At the voltage V2, the intensity of transmission light of blue is a maximum whereby the displayed colour is blue. At the voltage V3, the intensity of transmission light of green is a maximum whereby the displayed colour is green.
If the liquid crystal was driven by a voltage between the voltages Vl and V2, the displayed colour is intermediate between red and blue, namely red-blue, purple and blue-purple. Therefore the dis-play colour is easily changed by changing the drive voltage of said liquid crystal. When the time signal of minutes, hours, dates or months was selected, the drive voltage for said liguid crystal display device is selected by said switching circuit 6;
when said time signal displayed to said liquid crystal display device 9 was changed, the display colour is simultaneously changed whereby it is possible to acknowledge and judge the contents of time units of months, dates, hours and minutes by the display colour.
Figure 4 shows one detailed embodiment of the switching circuit 5 displayed in block diagram form.
In Figure 4, lOA, lOB, llA, llB, 12A, 12B, 13A and 13B are the gate circuits each having seven AND-circuits 14a and 14b - 14g;
the segment signals corresponding to the minute signal generated by the time keeping circuit 1 are applied to one input terminal of said AND-circuits 14a - 14g of said gate circuits lOA and lOB;
the other input terminals are connected together and to a station-ary contact 18 of the mechanical switch 7. The segment signals corresponding to the hours signal generated from said time keeping clrcùit 1 are applied to the one input terminal of said AND-circuits of said gate circuits llA and llB; the other input terminals are connected to one stationary contact 19 of said mechanical switch 7.
The segment signals corresponding to the dates signal generated from said time keeping circuit 1 are applied to the one input terminal of AND-circuits of said gate circuits 12A and 12B; the other input terminals are connected to a stationary contact 20 of the mechanical switch 7. The segment signals corresponding to the months signal generated from said time keeping circuit 1 are applied to the one input terminal of AND-circuits of said gate circuits 13A - 13C; the other input terminals are connected to a stationary contact 21 of said mechanical switch 7. The mechanical switch 7 has a movable contact 22 selectively connected to the stationary contacts 18, 19, 20 and 21; the movable contact 22 is connected to the terminal 23 at the voltage level corresponding to the logic lJ . The outputs of said gate circuits 10A, llA, 12A and 13A are applied to the gate circuit 15A. The outputs of said gate circuits 10B, llB, 12B and 13B are applied to the gate circuit 15B. Said gate circuits 15A and 15B are composed of four input-OR-circuits 16a - 16g; for example, the output of AND-circuit 14a of said gate circuits 10A, llA, 12A and 13A is applied 20 -to the OR-circuit 16a of said gate circuits 15A; the output of -AND-circuit 14g of said gate circuits 10B, llB, 12B and 13B is applied to the OR-circuit 16g of said gate circuit 15B. The outputs of said OR-circuits 16a - 16g of said gate circuit 15 are connected to the terminals 17Aa - 17Ag as the output terminal of said switching circuit 5; the outputs of said OR-circuits 16a -16g of said gate circuit 15B are connected to the terminals 17Ba -17Bg as the output terminal of said switching circuit 5. Accord-ing to said switching circuit 5, when said movable contact 22 of said mechanical switch 7 is connected to the stationary contact 21, the segment signal corresponding to time signal of months generated from said time keeping circuit 1 pass said gate circuits 10642f~5 13A and 13C, and further pass said gate circuits lSA and 15B, and are generated from said terminals 17Aa - 17Ag and 17Ba - 17Bg.
In the same manner, when said movable contact 22 is operated to the contact position to said stationary contact 20, the segment signals corresponding to the minutes signal pass said gate cir-cuits 12A, 12B, 15A and 15B, and are generated from the terminals 17Aa - 17Ag and 17Ba - 17Bg. According to the operation of said mechanical switch 7, the segment signals corresponding to minutes, hours, dates and months signals are selectively generated from said switching circuit 5.
Figure 5 shows one detailed embodiment of the switching circuit 6 of Figure 1, and has four transmission gates 24, 25, 26 and 27 and the inverters 28, 29, 30 and 31 corresponding to said transmission gates. The input terminals of said transmission gates 24, 25, 26 and 27 are respectively connected to the terminals al, a2, a3 and a4 of said voltage generating circuit 4; the output terminals of said transmission gates 24, 25, 26 and 27 are commonly connected to the terminal 32 as the output terminal of said switch-ing circuit 6. One control terminal of said transmission gates -24, 25, 26 and 27 is connected to the stationary terminals 18, 19, 20 and 21 of said mechanical switch 7 in Figures 1 and 4; the inverters 28, 29, 30 and 31 are respectively connected between said control terminal and the other control terminal. The voltage generated from said terminal al namely the highest voltage gener-ated from voltage generating circuit 4 is applied to the terminal 23 and to movable contact 22 of said mechanical switch 7. According to said switching circuit 6, when said mechanical switch 7 is operated to connect the movable contact 22 and stationary contact 20, said transmission gate 25 is turned ON whereby the voltage g-nerated at the terminal a2 of the voltage generating circuit 4 appears at the terminal 32. That is, the transmission gates 24, ~ ~ .
. , .:
25, 26 and 27 are reqpectively turned ON by the operation of said mechanical switch 7, whereby four output voltages from said voltage genèrating circuit 4 selectively appear at said terminal 32.
Figure 6 shows one detailed embodiment of said drive circuit 8 in Figure l; the same numerals are employed to the same part of Figures 1, 3 and 5. Figure 6 shows only the drive circuit to one display portion of said liquid crystal display device 9; however, the drive circuit to other one display portion is the same con-struction.
In Figure 6, numerals 33a - 33g are the exclusive O~-circuits in which the segment signals being generated from said terminals 17Aa - 17Ag of said switching circuit 5 are applied to one input terminal of the exclusive OR-circuits; the dividing signal of 32Hz obtained from said time keeping circuit 1 applied to the ter-minal 34 is applied to the other input terminal of said exclusive OR-circuits. The outputs of exclusive OR-circuits 33a - 33g are amplified to the output voltage level of said terminal al of said voltage generating circuit 4, namely the output voltage of said boosting circuit 3 by the level shifter 35a - 35g, and are applied to one control terminal of a pair of transmission gates 36a - 36g and 37a - 37g, and are applied to the other control terminal via said inverters 38a - 38g. The input terminal of said transmission gates 36a - 36g are commonly connected to the terminal 32 of said switching circuit 6; the input terminals of transmission gates 36a - 36g and 37a - 37g are commonly connected, and are respec-tively connected to said segment electrodes a - g in one display portion of said liquid display device 9. The dividing signal applied to the terminal 34 is amplified to the amplitude of the boosted voltage of said boosting circuit 3 by said level shifter 3g, and 18 applied to one control terminal of a pair of transmis-sion gates 40 and 41, and is inverted by the inverter 42 and is :, . .
.
applied to other control terminal. The input terminal of the transmission gate 40 is connected to the terminal 32; the input terminal of transmission gate 41 is connected to O-voltage level.
The output terminals of a pair of transmission gates 40 and 41 are commonly connected, and are connected to the figure electrode X
in one display portion of said liquid crystal display device 9.
According to said drive circuit 8 (Figure 1), when the seg-ment signal of high level H was generated from said terminal 17Aa (Figure 6), the dividing signal applied to the terminal 34 is the high level H; the outputs of exclusive OR-circuit 33a and level shifter 35a are lower level L whereby said transmission gate 36a is switched to ON position; the output voltage from terminal 32 is applied to the segment electrode "a". When the dividing signal is the high level, the transmission gate 41 is turned ON whereby the voltage of figure electrode X becomes "O". On the contrary, when the dividing signal becomes the lower level L, the transmis-sion gate 37a is turned ON whereby the voltage level of said seg-ment electrode "a" becomes "O"; further, said transmission gate 40 is turned ON whereby the voltage generated from said terminal 32 is applied to the figure electrode X. Therefore, during the segment that a signal of high level is generated, the output voltage of the terminal 32 is alternately applied to said segment "a" and figure electrode X in synchronism with the frequency of the dividing signal whereby the liquid crystal corresponding to the segment electrode "a" is alternately driven.
When the segment signal is not generated from said terminal 17Aa and it is lower level L, said transmission gate 37a is turned ON when said dividing signal is higher level H whereby said seg-ment electrode "a" becomes voltage level "O", similarly the figure electrode X, the output voltage of said terminal 32 is applied to said segment electrode "a", similarly said figure electrode X by said transmission gate 36a is turned ON when said dividing signal becomes lower level L. Therefore there is no electric field between said segment electrode "a" and figure electrode X whereby said liquid crystal corresponding to said segment electrode "a"
is not driven. The above noted operation is similarly applied to the other segment electrodes b - g; further drive voltage is the output voltage from the terminal 32 namely one of the voltages s al, a2, a3 and a4 of said voltage generating circuit 4 selected by the switching circuit 6.
The liquid display device 9 driven by said drive circuit 8 changes its display colour by the application of different drive voltages; in this embodiment the colour is changed to four kinds of colours. Therefore, the time units of months, dates, hours and minutes are selectively displayed at said liquid display device 9, and simultaneously these display colours are changed whereby it is possible to easily know and judge the contents of displayed time by watching the displayed colour.
In this embodiment, the time units of minutes, hours, months and dates are preferably selected, and displays with different colours. It is possible to display the time unit of seconds by employing the voltage generated from said voltage generating circuit 4. Further it is possible to display the time units of months and dates by the same colour or the different colours by employing four digits type liquid display device 9, and to display the time units of hours and minutes by the same colour or the different colours by employing four digits type liquid crystal display device 9. In this case, it is necessary to easily know the displayed contents by employing units of months-dates and hours-minutes.
mi~ invention is not limited to the above noted embodiment;
it is possible to change the construction and to improve. For example, the time signal is selected by the operation of mechanical switch; it is possible to cyclically display the time signal by employing the dividing signal obtained from certain dividing steps in the time keeping circuit.
According to the present invention, the time unit of seconds, minutes, hours, dates and months are preferably selected;
the driving voltage of said liquid crystal display device is changed in response to the displayed time units; further the displayed colour of the liquid crystal display is preferably changed by the retardation effect whereby the display portion of said liquid crystal display device is simplfied. It is possible to easily know and see the displayed time display, and to obtain a colourful display panel.
.
: 30 r ~ , .
In known digital liquid crystal timepieces, if the time units of seconds, minutes, hours, dates and months were dis-played on one display panel, it is necessary to provide a display portion of two digits for seconds, a display portion of four digits for minutes and hours, and a display portion of four digits for dates and months. Thus a total of ten digits is required in said display device. If each group of digits were constructed to a scale which can be easily read, said display panel become-excessively large. Therefore, it is very difficult to make a small wrist watch such as would be suitable for women.
The present invention is directed to the means for resolv-ing these problems, whereby a display panel employing only four digits is used to display months and dates, hours and minutes and seconds. With such a four digit display, it is possible to obtain a small sized display panel. However, it is very difficult to know the time unit being displayed. It is also necessary to pro-vide an additional means for distinguishing the displayed contents in normal display condition and time adjusting condition. The mounting of a further display has a disadvantage of being impossible to see the display from the stand point of perspective view. It is further possible to obtain a small sized wrist watch having two digits instead of four digits by selectively displaying said time units of seconds, minutes, hours, dates and months.
The object of the present invention is to provide a small sized wrist watch having a small sized display panel by reducing the number of digits in the display panel. Another object of the , , present invention is to provide a time display device having no other display portion for distinguishing the displayed time unit~
rospeotively. A further object of the present invent~on ~ to provide a digital liquid crystal electronic timepiece having a simple display panel. A further object of the present invention is to provide a digital liquid crystal electronic timepiece having a liquid crystal display device capable of displaying time unita of seconds, minutes, hours, dates and months in different colours respectively whereby it is possible to easily distinguish the digits being displayed.
A further object of the present invention is to provide large sized digits in the display panel by reducing the number o$
digits of the display device, whereby it is possible to obtain -colourful digital liquid crystal electronic timepiece by the change of display colour.
Referring now to the accompanying drawings which show a digital liquid crystal electronic timepiece of the present inven-tion:
Figure 1 shows a block diagram of the digital liquid crystal electronic timepiece of the present invention:
Figure 2 shows a characteristic for indicating a retarda-tion effect of the liquid crystal display device;
Figure 3 shows a circuit of one embodiment of the voltage generating circuit in Figure l;
Figure 4 shows a circuit of one embodiment of the switching circuit for selecting the display time signal;
Figure 5, which is on the same sheet as Figure 3, shows a circuit of one embodiment of the switching circuit for selecting the drive voltage of the liquid crystal display device; and Figure 6 shows a circuit of one embodiment of the drive circuit in Figure 1.
Figure 1 shows a block diagram for indicating a digital liquid crystal electronic timepiece of the present invention;
numeral 1 is a time keeping circuit. Said time keeping circuit 1 has an oscillating circuit (not shown) having a quartz element, a dividing circuit (not shown) for obtaining a standard signal of lHz, a time counter (not shown) for generating a time signal corresponding to the time units of seconds, minutes, hours, dates and months after counting said standard signal, and a decoder (not shown) for changing the output from said time counter to a prefer-able coded time signal. Therefore, four kinds of time signals aregenerated from said time keeping circuit 1. Said time keeping circuit 1 is operated by the output voltage of boosting circuit 3 and the battery voltage of the battery 2. Numeral 4 is a voltags generating circuit for generating four different voltages. Said voltage generating circuit 4, one embodiment as indicated in Figure 3, has a terminal al directly connected to the boosted voltage of said boosting circuit 3, a terminal a2 providing a voltage lower than said boosted voltage by the resistance Rl and zener diode ZDl, a terminal a3 providing a voltage lower than said boosted voltage and the output voltage of said terminal a2 by the resistance R2 and zener diode ZD2 and a terminal a4 providing a voltage lower than said boosted voltage and output voltage of said terminal a3 by the resistance R3 and zener diode ZD3. The boosted voltage is provided at terminal al; however, the output voltages of said terminals a2, a3 and a4 correspond to the zener voltages of said zener diodes ZDl, ZD2 and ZD3, and become lower respec-tively~ The resistance values of resistance Rl, R2 and R3 deter-mine the electric current of flowing to the zener diodes ZDl, ZD2 and ZD3, and are selected for generating voltages corresponding to the zener diode voltages to said terminals a2, a3 and a4.
` 1064265 - In Figure 1 the time signal of minutes, hour~, dates and months generated from said time keeping circuit 1 are applied to the switching circuit 5, and four voltages of the voltage gener-ating circuit 4 are applied to the switching circuit 6. The switching circuits 5 and 6 are controlled by a mechanical switch 7, for example the switch being operated by the operation of the stem of the electronic timepiece or other operational switch.
Said switching circuit 5 selects one signal of minuteQ, hours, dates and months and applies the selected signal to the driving circuit 8; the switching circuit 6 selects one of four voltages .
and applies it to the driving circuit 8. According to the present invention, when said switching circuit 5 selects the time signal of months, said switching circuit 6 selects the voltage from the terminal al of said voltage generating circuit 4. When said time signal of dates is selected, the voltage of terminal a3 is selected:
further when time signal of minutes is selected, the voltage of ~-terminal a4 is selected.
The driving circuit 8 drives the liquid crystal display device 9 with the voltage selected by said switching circuit 6, ; 20 and the time signal selected by said switching circuit 5 is dis-played by the liquid crystal display device 9. The liquid crystal display device 9 is composed of two digit display portions, each display portion having seven alpha-numeric type segment electrodes and one common figure electrode. The liquid crystal employed in said liquid crystal display device 9 has a retardation effect, the colour of said liquid crystal being changed by the difference of drive voltages.
Referring now to Figure 2, which shows the retardation effect of said liquid crystal, the X axis indicates the drive ~ltaqe ~pplied to the liquid crystal, the Y axis indicate~ the intensity of transmission light, the curved lines G, B and R
, ............ . .
,. :
.
10642~5 indicate the change of intensity of transmission light against the change of drive voltage of green, blue and red. At the voltage Vl, the intensity of transmission light of red is maximum whereby the displayed colour is red. At the voltage V2, the intensity of transmission light of blue is a maximum whereby the displayed colour is blue. At the voltage V3, the intensity of transmission light of green is a maximum whereby the displayed colour is green.
If the liquid crystal was driven by a voltage between the voltages Vl and V2, the displayed colour is intermediate between red and blue, namely red-blue, purple and blue-purple. Therefore the dis-play colour is easily changed by changing the drive voltage of said liquid crystal. When the time signal of minutes, hours, dates or months was selected, the drive voltage for said liguid crystal display device is selected by said switching circuit 6;
when said time signal displayed to said liquid crystal display device 9 was changed, the display colour is simultaneously changed whereby it is possible to acknowledge and judge the contents of time units of months, dates, hours and minutes by the display colour.
Figure 4 shows one detailed embodiment of the switching circuit 5 displayed in block diagram form.
In Figure 4, lOA, lOB, llA, llB, 12A, 12B, 13A and 13B are the gate circuits each having seven AND-circuits 14a and 14b - 14g;
the segment signals corresponding to the minute signal generated by the time keeping circuit 1 are applied to one input terminal of said AND-circuits 14a - 14g of said gate circuits lOA and lOB;
the other input terminals are connected together and to a station-ary contact 18 of the mechanical switch 7. The segment signals corresponding to the hours signal generated from said time keeping clrcùit 1 are applied to the one input terminal of said AND-circuits of said gate circuits llA and llB; the other input terminals are connected to one stationary contact 19 of said mechanical switch 7.
The segment signals corresponding to the dates signal generated from said time keeping circuit 1 are applied to the one input terminal of AND-circuits of said gate circuits 12A and 12B; the other input terminals are connected to a stationary contact 20 of the mechanical switch 7. The segment signals corresponding to the months signal generated from said time keeping circuit 1 are applied to the one input terminal of AND-circuits of said gate circuits 13A - 13C; the other input terminals are connected to a stationary contact 21 of said mechanical switch 7. The mechanical switch 7 has a movable contact 22 selectively connected to the stationary contacts 18, 19, 20 and 21; the movable contact 22 is connected to the terminal 23 at the voltage level corresponding to the logic lJ . The outputs of said gate circuits 10A, llA, 12A and 13A are applied to the gate circuit 15A. The outputs of said gate circuits 10B, llB, 12B and 13B are applied to the gate circuit 15B. Said gate circuits 15A and 15B are composed of four input-OR-circuits 16a - 16g; for example, the output of AND-circuit 14a of said gate circuits 10A, llA, 12A and 13A is applied 20 -to the OR-circuit 16a of said gate circuits 15A; the output of -AND-circuit 14g of said gate circuits 10B, llB, 12B and 13B is applied to the OR-circuit 16g of said gate circuit 15B. The outputs of said OR-circuits 16a - 16g of said gate circuit 15 are connected to the terminals 17Aa - 17Ag as the output terminal of said switching circuit 5; the outputs of said OR-circuits 16a -16g of said gate circuit 15B are connected to the terminals 17Ba -17Bg as the output terminal of said switching circuit 5. Accord-ing to said switching circuit 5, when said movable contact 22 of said mechanical switch 7 is connected to the stationary contact 21, the segment signal corresponding to time signal of months generated from said time keeping circuit 1 pass said gate circuits 10642f~5 13A and 13C, and further pass said gate circuits lSA and 15B, and are generated from said terminals 17Aa - 17Ag and 17Ba - 17Bg.
In the same manner, when said movable contact 22 is operated to the contact position to said stationary contact 20, the segment signals corresponding to the minutes signal pass said gate cir-cuits 12A, 12B, 15A and 15B, and are generated from the terminals 17Aa - 17Ag and 17Ba - 17Bg. According to the operation of said mechanical switch 7, the segment signals corresponding to minutes, hours, dates and months signals are selectively generated from said switching circuit 5.
Figure 5 shows one detailed embodiment of the switching circuit 6 of Figure 1, and has four transmission gates 24, 25, 26 and 27 and the inverters 28, 29, 30 and 31 corresponding to said transmission gates. The input terminals of said transmission gates 24, 25, 26 and 27 are respectively connected to the terminals al, a2, a3 and a4 of said voltage generating circuit 4; the output terminals of said transmission gates 24, 25, 26 and 27 are commonly connected to the terminal 32 as the output terminal of said switch-ing circuit 6. One control terminal of said transmission gates -24, 25, 26 and 27 is connected to the stationary terminals 18, 19, 20 and 21 of said mechanical switch 7 in Figures 1 and 4; the inverters 28, 29, 30 and 31 are respectively connected between said control terminal and the other control terminal. The voltage generated from said terminal al namely the highest voltage gener-ated from voltage generating circuit 4 is applied to the terminal 23 and to movable contact 22 of said mechanical switch 7. According to said switching circuit 6, when said mechanical switch 7 is operated to connect the movable contact 22 and stationary contact 20, said transmission gate 25 is turned ON whereby the voltage g-nerated at the terminal a2 of the voltage generating circuit 4 appears at the terminal 32. That is, the transmission gates 24, ~ ~ .
. , .:
25, 26 and 27 are reqpectively turned ON by the operation of said mechanical switch 7, whereby four output voltages from said voltage genèrating circuit 4 selectively appear at said terminal 32.
Figure 6 shows one detailed embodiment of said drive circuit 8 in Figure l; the same numerals are employed to the same part of Figures 1, 3 and 5. Figure 6 shows only the drive circuit to one display portion of said liquid crystal display device 9; however, the drive circuit to other one display portion is the same con-struction.
In Figure 6, numerals 33a - 33g are the exclusive O~-circuits in which the segment signals being generated from said terminals 17Aa - 17Ag of said switching circuit 5 are applied to one input terminal of the exclusive OR-circuits; the dividing signal of 32Hz obtained from said time keeping circuit 1 applied to the ter-minal 34 is applied to the other input terminal of said exclusive OR-circuits. The outputs of exclusive OR-circuits 33a - 33g are amplified to the output voltage level of said terminal al of said voltage generating circuit 4, namely the output voltage of said boosting circuit 3 by the level shifter 35a - 35g, and are applied to one control terminal of a pair of transmission gates 36a - 36g and 37a - 37g, and are applied to the other control terminal via said inverters 38a - 38g. The input terminal of said transmission gates 36a - 36g are commonly connected to the terminal 32 of said switching circuit 6; the input terminals of transmission gates 36a - 36g and 37a - 37g are commonly connected, and are respec-tively connected to said segment electrodes a - g in one display portion of said liquid display device 9. The dividing signal applied to the terminal 34 is amplified to the amplitude of the boosted voltage of said boosting circuit 3 by said level shifter 3g, and 18 applied to one control terminal of a pair of transmis-sion gates 40 and 41, and is inverted by the inverter 42 and is :, . .
.
applied to other control terminal. The input terminal of the transmission gate 40 is connected to the terminal 32; the input terminal of transmission gate 41 is connected to O-voltage level.
The output terminals of a pair of transmission gates 40 and 41 are commonly connected, and are connected to the figure electrode X
in one display portion of said liquid crystal display device 9.
According to said drive circuit 8 (Figure 1), when the seg-ment signal of high level H was generated from said terminal 17Aa (Figure 6), the dividing signal applied to the terminal 34 is the high level H; the outputs of exclusive OR-circuit 33a and level shifter 35a are lower level L whereby said transmission gate 36a is switched to ON position; the output voltage from terminal 32 is applied to the segment electrode "a". When the dividing signal is the high level, the transmission gate 41 is turned ON whereby the voltage of figure electrode X becomes "O". On the contrary, when the dividing signal becomes the lower level L, the transmis-sion gate 37a is turned ON whereby the voltage level of said seg-ment electrode "a" becomes "O"; further, said transmission gate 40 is turned ON whereby the voltage generated from said terminal 32 is applied to the figure electrode X. Therefore, during the segment that a signal of high level is generated, the output voltage of the terminal 32 is alternately applied to said segment "a" and figure electrode X in synchronism with the frequency of the dividing signal whereby the liquid crystal corresponding to the segment electrode "a" is alternately driven.
When the segment signal is not generated from said terminal 17Aa and it is lower level L, said transmission gate 37a is turned ON when said dividing signal is higher level H whereby said seg-ment electrode "a" becomes voltage level "O", similarly the figure electrode X, the output voltage of said terminal 32 is applied to said segment electrode "a", similarly said figure electrode X by said transmission gate 36a is turned ON when said dividing signal becomes lower level L. Therefore there is no electric field between said segment electrode "a" and figure electrode X whereby said liquid crystal corresponding to said segment electrode "a"
is not driven. The above noted operation is similarly applied to the other segment electrodes b - g; further drive voltage is the output voltage from the terminal 32 namely one of the voltages s al, a2, a3 and a4 of said voltage generating circuit 4 selected by the switching circuit 6.
The liquid display device 9 driven by said drive circuit 8 changes its display colour by the application of different drive voltages; in this embodiment the colour is changed to four kinds of colours. Therefore, the time units of months, dates, hours and minutes are selectively displayed at said liquid display device 9, and simultaneously these display colours are changed whereby it is possible to easily know and judge the contents of displayed time by watching the displayed colour.
In this embodiment, the time units of minutes, hours, months and dates are preferably selected, and displays with different colours. It is possible to display the time unit of seconds by employing the voltage generated from said voltage generating circuit 4. Further it is possible to display the time units of months and dates by the same colour or the different colours by employing four digits type liquid display device 9, and to display the time units of hours and minutes by the same colour or the different colours by employing four digits type liquid crystal display device 9. In this case, it is necessary to easily know the displayed contents by employing units of months-dates and hours-minutes.
mi~ invention is not limited to the above noted embodiment;
it is possible to change the construction and to improve. For example, the time signal is selected by the operation of mechanical switch; it is possible to cyclically display the time signal by employing the dividing signal obtained from certain dividing steps in the time keeping circuit.
According to the present invention, the time unit of seconds, minutes, hours, dates and months are preferably selected;
the driving voltage of said liquid crystal display device is changed in response to the displayed time units; further the displayed colour of the liquid crystal display is preferably changed by the retardation effect whereby the display portion of said liquid crystal display device is simplfied. It is possible to easily know and see the displayed time display, and to obtain a colourful display panel.
.
: 30 r ~ , .
Claims (6)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1, An electronic timepiece with a digital liquid crystal display, comprising a time signal pulse generating circuit, a time counting circuit for generating time signals corresponding to seconds, minutes, hours and dates, liquid crystal display means having retardation effect for displaying a digital time Signal in different colours according to the drive voltage applied, a first switching circuit means for selectively supplying different time signals from said time counting circuit to said display means for visual display thereby, a voltage generating circuit for gen-erating a plurality of different drive voltages for driving said liquid crystal display means, and a second switching circuit means Coordinated with said first switching circuit means to supply from said voltage generating circuit to said liquid crystal display means a selected drive voltage corresponding to the selected time signal to be displayed, whereby different time signals are distin-guished from one another by being displayed in different colours.
2. An electronic timepiece according to claim 1, in which said liquid crystal display means consists of means for dis-playing two digits.
3. An electronic timepiece according to claim 1, comprising manually operable switch means jointly controlling said first switch-ing circuit means and said second switching circuit means.
4. An electronic timepiece according to claim 1, com-prising a driving circuit for driving said liquid crystal display means, said driving circuit having inputs connected respectively to said first switching circuit means and said second switching circuit means and outputs connected to said liquid crystal dis-play means.
5. An electronic timepiece according to claim 2, in which said voltage generating circuit comprises means for gen-erating four different drive voltages for said liquid crystal display means.
6. An electronic timepiece according to claim 5, in which said liquid crystal display means comprises segment electrodes and a figure electrode and in which said driving circuit comprises means controlled by voltage pulses supplied by said time signal pulse generating circuit for supplying a selected drive voltage alternately to said selected ones of said segment electrodes and said figure electrode to display a selected time signal in a selected colour.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP50097387A JPS5221861A (en) | 1975-08-11 | 1975-08-11 | Digital liquid-clystal electronic watch |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1064265A true CA1064265A (en) | 1979-10-16 |
Family
ID=14191091
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA258,698A Expired CA1064265A (en) | 1975-08-11 | 1976-08-09 | Digital liquid crystal electronic timepiece |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US4044546A (en) |
| JP (1) | JPS5221861A (en) |
| BR (1) | BR7605159A (en) |
| CA (1) | CA1064265A (en) |
| DE (1) | DE2636194A1 (en) |
| FR (1) | FR2321145A1 (en) |
| GB (1) | GB1514857A (en) |
| HK (1) | HK85179A (en) |
| IT (1) | IT1073651B (en) |
Families Citing this family (30)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52128100A (en) * | 1976-04-21 | 1977-10-27 | Toshiba Corp | Driver circuit |
| JPS5324798A (en) * | 1976-08-20 | 1978-03-07 | Sharp Corp | Driving circuit of electrochromic display device |
| JPS5381264A (en) * | 1976-12-27 | 1978-07-18 | Toshiba Corp | Designing system for electronic watch |
| JPS53107366A (en) * | 1977-03-01 | 1978-09-19 | Citizen Watch Co Ltd | Electronic watch having matrix drive display |
| JPS5438165A (en) * | 1977-09-01 | 1979-03-22 | Seiko Instr & Electronics Ltd | Electronic watch |
| JPS5492094A (en) * | 1977-12-29 | 1979-07-20 | Seiko Epson Corp | Power supply method for liquid crystal display substance |
| JPS54126497A (en) * | 1978-03-24 | 1979-10-01 | Sharp Corp | Dap-type liquid crystal display device |
| US4223525A (en) * | 1978-10-11 | 1980-09-23 | Societe Suisse Pour L'industrie Horlogere Management Services, S.A. | Sequential display for digital chronograph |
| JPS6026344B2 (en) * | 1979-04-10 | 1985-06-22 | 富士通株式会社 | Clock signal generation method |
| JPS6051669B2 (en) * | 1979-05-23 | 1985-11-15 | 株式会社精工舎 | electronic clock |
| US4272195A (en) * | 1979-06-05 | 1981-06-09 | Beckman Instruments, Inc. | Method and apparatus for determining the wavelength of light |
| JPS5677891A (en) * | 1979-11-29 | 1981-06-26 | Tokyo Shibaura Electric Co | Displayyunit drive circuit |
| JPS6243625A (en) * | 1985-08-21 | 1987-02-25 | Tokyo Electric Co Ltd | Liquid crystal display device |
| US4647217A (en) * | 1986-01-08 | 1987-03-03 | Karel Havel | Variable color digital timepiece |
| US5122733A (en) * | 1986-01-15 | 1992-06-16 | Karel Havel | Variable color digital multimeter |
| US4702615A (en) * | 1986-12-24 | 1987-10-27 | Karel Havel | Analog display timepiece |
| CA1243492A (en) * | 1987-03-26 | 1988-10-25 | Karel Havel | Analog display timepiece |
| US5302946A (en) * | 1988-07-21 | 1994-04-12 | Leonid Shapiro | Stacked display panel construction and method of making same |
| US5089810A (en) * | 1990-04-09 | 1992-02-18 | Computer Accessories Corporation | Stacked display panel construction and method of making same |
| US5153568A (en) * | 1988-07-21 | 1992-10-06 | Proxima Corporation | Liquid crystal display panel system and method of using same |
| US4917465A (en) * | 1989-03-28 | 1990-04-17 | In Focus Systems, Inc. | Color display system |
| USRE36654E (en) * | 1989-03-28 | 2000-04-11 | In Focus Systems, Inc. | Stacked LCD color display |
| US5050965A (en) * | 1989-09-01 | 1991-09-24 | In Focus Systems, Inc. | Color display using supertwisted nematic liquid crystal material |
| US5946636A (en) * | 1996-10-02 | 1999-08-31 | Ericsson Inc. | Quick-recognition visual notification system for use in radiotelephones |
| US6937267B1 (en) * | 1998-12-22 | 2005-08-30 | Pentax Corporation | Electronic endoscope |
| US6987710B2 (en) * | 2001-11-30 | 2006-01-17 | Equity Industries, Inc. | Alarm clock with dial illumination |
| US7054233B2 (en) * | 2001-11-30 | 2006-05-30 | Equity Industries, Inc. | Wall clock with dial illumination |
| WO2003048821A1 (en) * | 2001-11-30 | 2003-06-12 | Equity Industries Corp. | Clocks with diffusion reflector lighting |
| US6958384B2 (en) * | 2002-03-15 | 2005-10-25 | Wisconsin Alumni Research Foundation | Polypeptides containing γ-amino acids |
| US7079452B2 (en) * | 2002-04-16 | 2006-07-18 | Harrison Shelton E | Time display system, method and device |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4929472B1 (en) * | 1969-11-29 | 1974-08-05 | ||
| IT952097B (en) * | 1971-03-08 | 1973-07-20 | Suwa Seikosha Kk | IMPROVEMENT IN NUMERICAL INDICATION TIME MEASUREMENT SYSTEMS |
| FR2188212B1 (en) * | 1972-06-13 | 1977-11-04 | Lip Horlogerie | |
| JPS5426139B2 (en) * | 1973-05-23 | 1979-09-01 | ||
| JPS5616431B2 (en) * | 1973-06-18 | 1981-04-16 | ||
| US3956880A (en) * | 1973-10-18 | 1976-05-18 | Time Computer, Inc. | Solid state wristwatch with charge coupled divider |
| JPS50101068A (en) * | 1974-01-08 | 1975-08-11 | ||
| GB1491471A (en) * | 1974-01-21 | 1977-11-09 | Secr Defence | Colour display systems |
| US3922847A (en) * | 1974-05-06 | 1975-12-02 | Texas Instruments Inc | VLED solid state watch |
-
1975
- 1975-08-11 JP JP50097387A patent/JPS5221861A/en active Pending
-
1976
- 1976-07-26 GB GB31086/76A patent/GB1514857A/en not_active Expired
- 1976-08-02 IT IT50729/76A patent/IT1073651B/en active
- 1976-08-06 BR BR7605159A patent/BR7605159A/en unknown
- 1976-08-06 FR FR7624129A patent/FR2321145A1/en active Granted
- 1976-08-09 CA CA258,698A patent/CA1064265A/en not_active Expired
- 1976-08-10 US US05/713,227 patent/US4044546A/en not_active Expired - Lifetime
- 1976-08-11 DE DE19762636194 patent/DE2636194A1/en not_active Ceased
-
1979
- 1979-12-13 HK HK851/79A patent/HK85179A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5221861A (en) | 1977-02-18 |
| GB1514857A (en) | 1978-06-21 |
| BR7605159A (en) | 1977-08-02 |
| IT1073651B (en) | 1985-04-17 |
| US4044546A (en) | 1977-08-30 |
| FR2321145A1 (en) | 1977-03-11 |
| DE2636194A1 (en) | 1977-02-24 |
| FR2321145B1 (en) | 1981-08-21 |
| HK85179A (en) | 1979-12-21 |
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